/*
  ==============================================================================

   This file is part of the JUCE framework.
   Copyright (c) Raw Material Software Limited

   JUCE is an open source framework subject to commercial or open source
   licensing.

   By downloading, installing, or using the JUCE framework, or combining the
   JUCE framework with any other source code, object code, content or any other
   copyrightable work, you agree to the terms of the JUCE End User Licence
   Agreement, and all incorporated terms including the JUCE Privacy Policy and
   the JUCE Website Terms of Service, as applicable, which will bind you. If you
   do not agree to the terms of these agreements, we will not license the JUCE
   framework to you, and you must discontinue the installation or download
   process and cease use of the JUCE framework.

   JUCE End User Licence Agreement: https://juce.com/legal/juce-8-licence/
   JUCE Privacy Policy: https://juce.com/juce-privacy-policy
   JUCE Website Terms of Service: https://juce.com/juce-website-terms-of-service/

   Or:

   You may also use this code under the terms of the AGPLv3:
   https://www.gnu.org/licenses/agpl-3.0.en.html

   THE JUCE FRAMEWORK IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL
   WARRANTIES, WHETHER EXPRESSED OR IMPLIED, INCLUDING WARRANTY OF
   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, ARE DISCLAIMED.

  ==============================================================================
*/

namespace juce
{

ARAAudioSourceReader::ARAAudioSourceReader (ARAAudioSource* audioSource)
    : AudioFormatReader (nullptr, "ARAAudioSourceReader"),
      audioSourceBeingRead (audioSource)
{
    jassert (audioSourceBeingRead != nullptr);

    bitsPerSample = 32;
    usesFloatingPointData = true;
    sampleRate = audioSourceBeingRead->getSampleRate();
    numChannels = (unsigned int) audioSourceBeingRead->getChannelCount();
    lengthInSamples = audioSourceBeingRead->getSampleCount();
    tmpPtrs.resize (numChannels);

    audioSourceBeingRead->addListener (this);

    if (audioSourceBeingRead->isSampleAccessEnabled())
        hostReader.reset (new ARA::PlugIn::HostAudioReader (audioSourceBeingRead));
}

ARAAudioSourceReader::~ARAAudioSourceReader()
{
    invalidate();
}

void ARAAudioSourceReader::invalidate()
{
    ScopedWriteLock scopedLock (lock);

    if (! isValid())
        return;

    hostReader.reset();

    audioSourceBeingRead->removeListener (this);
    audioSourceBeingRead = nullptr;
}

void ARAAudioSourceReader::willUpdateAudioSourceProperties (ARAAudioSource* audioSource,
                                                            ARAAudioSource::PropertiesPtr newProperties)
{
    if (audioSource->getSampleCount() != newProperties->sampleCount
        || ! exactlyEqual (audioSource->getSampleRate(), newProperties->sampleRate)
        || audioSource->getChannelCount() != newProperties->channelCount)
    {
        invalidate();
    }
}

void ARAAudioSourceReader::doUpdateAudioSourceContent ([[maybe_unused]] ARAAudioSource* audioSource,
                                                       ARAContentUpdateScopes scopeFlags)
{
    jassert (audioSourceBeingRead == audioSource);

    // Don't invalidate if the audio signal is unchanged
    if (scopeFlags.affectSamples())
        invalidate();
}

void ARAAudioSourceReader::willEnableAudioSourceSamplesAccess ([[maybe_unused]] ARAAudioSource* audioSource, bool enable)
{
    jassert (audioSourceBeingRead == audioSource);

    // Invalidate our reader if sample access is disabled
    if (! enable)
    {
        ScopedWriteLock scopedLock (lock);
        hostReader.reset();
    }
}

void ARAAudioSourceReader::didEnableAudioSourceSamplesAccess ([[maybe_unused]] ARAAudioSource* audioSource, bool enable)
{
    jassert (audioSourceBeingRead == audioSource);

    // Recreate our reader if sample access is enabled
    if (enable && isValid())
    {
        ScopedWriteLock scopedLock (lock);
        hostReader.reset (new ARA::PlugIn::HostAudioReader (audioSourceBeingRead));
    }
}

void ARAAudioSourceReader::willDestroyAudioSource ([[maybe_unused]] ARAAudioSource* audioSource)
{
    jassert (audioSourceBeingRead == audioSource);

    invalidate();
}

bool ARAAudioSourceReader::readSamples (int* const* destSamples, int numDestChannels, int startOffsetInDestBuffer,
                                        int64 startSampleInFile, int numSamples)
{
    const auto destSize = (bitsPerSample / 8) * (size_t) numSamples;
    const auto bufferOffset = (int) (bitsPerSample / 8) * startOffsetInDestBuffer;

    if (isValid())
    {
        const ScopedTryReadLock readLock (lock);

        if (readLock.isLocked() && hostReader != nullptr)
        {
            for (size_t i = 0; i < tmpPtrs.size(); ++i)
            {
                if ((i < (size_t) numDestChannels) && (destSamples[i] != nullptr))
                {
                    tmpPtrs[i] = ((uint8_t*) destSamples[i]) + bufferOffset;
                }
                else
                {
                    // We need to provide destination pointers for all channels in the ARA read call, even if
                    // readSamples is not reading all of them. Hence we use this dummy buffer to pad the read
                    // destination area.
                    static thread_local std::vector<uint8_t> dummyBuffer;

                    if (destSize > dummyBuffer.size())
                        dummyBuffer.resize (destSize);

                    tmpPtrs[i] = dummyBuffer.data();
                }
            }

            return hostReader->readAudioSamples (startSampleInFile, numSamples, tmpPtrs.data());
        }
    }

    for (int i = 0; i < numDestChannels; ++i)
        if (destSamples[i] != nullptr)
            zeromem (((uint8_t*) destSamples[i]) + bufferOffset, destSize);

    return false;
}

//==============================================================================
ARAPlaybackRegionReader::ARAPlaybackRegionReader (ARAPlaybackRegion* playbackRegion)
    : ARAPlaybackRegionReader (playbackRegion->getAudioModification()->getAudioSource()->getSampleRate(),
                               playbackRegion->getAudioModification()->getAudioSource()->getChannelCount(),
                               { playbackRegion })
{}

ARAPlaybackRegionReader::ARAPlaybackRegionReader (double rate, int numChans,
                                                  const std::vector<ARAPlaybackRegion*>& playbackRegions)
    : AudioFormatReader (nullptr, "ARAPlaybackRegionReader")
{
    // We're only providing the minimal set of meaningful values, since the ARA renderer should only
    // look at the time position and the playing state, and read any related tempo or bar signature
    // information from the ARA model directly (MusicalContext).
    positionInfo.setIsPlaying (true);

    sampleRate = rate;
    numChannels = (unsigned int) numChans;
    bitsPerSample = 32;
    usesFloatingPointData = true;

    auto* documentController = (! playbackRegions.empty())
                                   ? playbackRegions.front()->getDocumentController<ARADocumentController>()
                                   : nullptr;

    playbackRenderer.reset (documentController ? static_cast<ARAPlaybackRenderer*> (documentController->doCreatePlaybackRenderer())
                                               : nullptr);

    if (playbackRenderer != nullptr)
    {
        double regionsStartTime = std::numeric_limits<double>::max();
        double regionsEndTime = std::numeric_limits<double>::lowest();

        for (const auto& playbackRegion : playbackRegions)
        {
            jassert (playbackRegion->getDocumentController() == documentController);
            auto playbackRegionTimeRange = playbackRegion->getTimeRange (ARAPlaybackRegion::IncludeHeadAndTail::yes);
            regionsStartTime = jmin (regionsStartTime, playbackRegionTimeRange.getStart());
            regionsEndTime = jmax (regionsEndTime, playbackRegionTimeRange.getEnd());

            playbackRenderer->addPlaybackRegion (ARA::PlugIn::toRef (playbackRegion));
            playbackRegion->addListener (this);
        }

        startInSamples = (int64) (regionsStartTime * sampleRate + 0.5);
        lengthInSamples = (int64) ((regionsEndTime - regionsStartTime) * sampleRate + 0.5);

        playbackRenderer->prepareToPlay (rate,
                                         maximumBlockSize,
                                         numChans,
                                         AudioProcessor::ProcessingPrecision::singlePrecision,
                                         ARARenderer::AlwaysNonRealtime::yes);
    }
    else
    {
        startInSamples = 0;
        lengthInSamples = 0;
    }
}

ARAPlaybackRegionReader::~ARAPlaybackRegionReader()
{
    invalidate();
}

void ARAPlaybackRegionReader::invalidate()
{
    ScopedWriteLock scopedWrite (lock);

    if (! isValid())
        return;

    for (auto& playbackRegion : playbackRenderer->getPlaybackRegions())
        playbackRegion->removeListener (this);

    playbackRenderer->releaseResources();
    playbackRenderer.reset();
}

bool ARAPlaybackRegionReader::readSamples (int* const* destSamples, int numDestChannels, int startOffsetInDestBuffer,
                                           int64 startSampleInFile, int numSamples)
{
    bool success = false;
    bool needClearSamples = true;

    const ScopedTryReadLock readLock (lock);

    if (readLock.isLocked())
    {
        if (isValid())
        {
            success = true;
            needClearSamples = false;
            positionInfo.setTimeInSamples (startSampleInFile + startInSamples);

            while (numSamples > 0)
            {
                const int numSliceSamples = jmin (numSamples, maximumBlockSize);
                AudioBuffer<float> buffer ((float **) destSamples, numDestChannels, startOffsetInDestBuffer, numSliceSamples);
                positionInfo.setTimeInSeconds (static_cast<double> (*positionInfo.getTimeInSamples()) / sampleRate);
                success &= playbackRenderer->processBlock (buffer, AudioProcessor::Realtime::no, positionInfo);
                numSamples -= numSliceSamples;
                startOffsetInDestBuffer += numSliceSamples;
                positionInfo.setTimeInSamples (*positionInfo.getTimeInSamples() + numSliceSamples);
            }
        }
    }

    if (needClearSamples)
        for (int chan_i = 0; chan_i < numDestChannels; ++chan_i)
            FloatVectorOperations::clear ((float *) destSamples[chan_i], numSamples);

    return success;
}

void ARAPlaybackRegionReader::willUpdatePlaybackRegionProperties (ARAPlaybackRegion* playbackRegion, ARAPlaybackRegion::PropertiesPtr newProperties)
{
    jassert (ARA::contains (playbackRenderer->getPlaybackRegions(), playbackRegion));

    if ((! exactlyEqual (playbackRegion->getStartInAudioModificationTime(), newProperties->startInModificationTime))
        || ! exactlyEqual (playbackRegion->getDurationInAudioModificationTime(), newProperties->durationInModificationTime)
        || ! exactlyEqual (playbackRegion->getStartInPlaybackTime(), newProperties->startInPlaybackTime)
        || ! exactlyEqual (playbackRegion->getDurationInPlaybackTime(), newProperties->durationInPlaybackTime)
        || (playbackRegion->isTimestretchEnabled() != ((newProperties->transformationFlags & ARA::kARAPlaybackTransformationTimestretch) != 0))
        || (playbackRegion->isTimeStretchReflectingTempo() != ((newProperties->transformationFlags & ARA::kARAPlaybackTransformationTimestretchReflectingTempo) != 0))
        || (playbackRegion->hasContentBasedFadeAtHead() != ((newProperties->transformationFlags & ARA::kARAPlaybackTransformationContentBasedFadeAtHead) != 0))
        || (playbackRegion->hasContentBasedFadeAtTail() != ((newProperties->transformationFlags & ARA::kARAPlaybackTransformationContentBasedFadeAtTail) != 0)))
    {
        invalidate();
    }
}

void ARAPlaybackRegionReader::didUpdatePlaybackRegionContent ([[maybe_unused]] ARAPlaybackRegion* playbackRegion,
                                                              ARAContentUpdateScopes scopeFlags)
{
    jassert (ARA::contains (playbackRenderer->getPlaybackRegions(), playbackRegion));

    // Invalidate if the audio signal is changed
    if (scopeFlags.affectSamples())
        invalidate();
}

void ARAPlaybackRegionReader::willDestroyPlaybackRegion ([[maybe_unused]] ARAPlaybackRegion* playbackRegion)
{
    jassert (ARA::contains (playbackRenderer->getPlaybackRegions(), playbackRegion));

    invalidate();
}

} // namespace juce
